South Sydney are the NRL's benchmark team according to Sydney Roosters back-rower Boyd Cordner despite the tricolours' premiership win.

The arch enemies continue their century-old rivalry on Thursday in the NRL season opener, with the Roosters beginning their campaign to be the first side to claim back-to-back titles since Brisbane in 1992-93.

The Rabbitohs, on the other hand, were desperate to leave the heartbreak of last season's preliminary final loss to Manly behind them.

The Roosters prevailed in an epic grand final against the Sea Eagles last year with the Rabbitohs watching from afar, but Cordner said Souths were the team to beat in 2014.

''They have been one of the favourites for the last few years now. Personally, I think they have been the benchmark or close to the last few years so they are going to be thereabouts again this year for sure,'' Cordner said at training today.

''It's massive, round one. There has always been that good rivalry between the clubs.

''With that rivalry there is always that extra feeling. Round one is always the game we are looking forward to.''

Souths come into the clash with an injury cloud over halves Adam Reynolds (knee) and Dylan Walker (ankle), with young gun Luke Keary (shoulder) sidelined for five months and prop Tom Burgess (foot) set to miss around two months.

In contrast, the Roosters are only missing the retired Luke O'Donnell from their premiership-winning side.

Prop Dylan Napa comes into the premiers side to replace O'Donnell.

''This is a new season now but it is a massive thing for us consistency,'' Cordner said.

''We built our season last year very well. We started off the season very well and we were very consistent throughout the year and I think we can do that again this year.''